Identification and analysis of electromagnetic signals in Greece: The case of the Kozani earthquake VAN prediction

An electric station was installed in July 1993, 4.5 km away from the VAN station of Ioannina, and recorded in the following two years a number of anomalous signals, including those of April 18 and 19, 1995, interpreted by the VAN group as Seismic Electric Signals precursors to the May 13 Kozani earthquake (West-Macedonia). A magnetic station was also installed and clearly recorded the magnetic components of the same events. The amplitude, shape, characteristic pattern and duration, magnetic characteristics and polarisation of the anomalous signals suggest that they are generated by artificial (industrial) sources. Copyright 1996 by the American Geophysical Union

Geomagnetic Observations for Main Field Studies:from Ground to Space

Direct measurements of the geomagnetic field have been made for more than 400 years, beginning with individual determinations of the angle between geographic and magnetic North. This was followed by the start of continuous time series of full vector measurements at geomagnetic observatories and the beginning of geomagnetic repeat stations surveys in the 19th century. In the second half of the 20th century, true global coverage with geomagnetic field measurements was accomplished by magnetometer payloads on low-Earth-orbiting satellites. This article describes the procedures and instruments for magnetic field measurements on ground and in space and covers geomagnetic observatories, repeat stations, automatic observatories, satellites and historic observations. Special emphasis is laid on the global network of geomagnetic observatories